1. Field of the Invention
This invention relates to a treadmill, and more particularly to a foldable treadmill which can be folded to an inoperative position and unfolded to an operative position ready for a user to exercise thereon.
2. Description of the Related Prior Art
Typical reorienting treadmills having a tread base that is rotatably attached to a support structure and orientable from a first position for performing exercises to a second position for storage, are disclosed in U.S. Pat. No. 5,772,560 (Watterson) and U.S. Pat. No. 5,676,524 (Watterson). U.S. Pat. No. 5,772,560 shows a treadmill (FIGS. 1 and 2) that includes a tread base 100 and a support structure 200. The support structure 200 has feet means and an upright structure extending upwardly from the feet means. The front portion of the tread base 100 is rotatably connected to the support structure 200 to rotate about an axis, so that the tread base 100 can be oriented from a first position ready for a user to perform exercises (see FIG. 1), to a second position for storing the treadmill (see FIG. 2).
The aforementioned treadmill, though having the function of rotating the tread base about an axis so as to reorient the same from a folded position to an unfolded position, has the following drawbacks:
1. Since the tread base 100 is pivoted to the upright structure of the support structure 200 rather than the feet means and since the pivot axis thereof is at a height distant from the supporting surface so as to allow free rotation of the tread base, the center of gravity of the tread base 100 can not be lowered. If one tries to lower the pivotal axis of the tread base 100, the front end of the tread base 100 can interfere with the floor surface and rotation of the tread base 100 to a vertical position will become impossible.
2. Since the weight of the tread base 100 is borne by the upright structure at the pivot joint thereof either at the folded position or the unfolded position of the treadmill, the treadmill is prone to wear at the pivot joint of the tread base 100 and the support structure 200. A strong structural material is needed for the pivot joint and the upright structure in order to bear the weight of the tread base 100 and to bear the dynamic forces produced during the exercise action of the user.
3. As can be understood from FIG. 2, the treadmill has to be tilted to an angle so as to raise the rear ends of the feet means and to place rollers 201 mounted at the front ends of the feet means in contact with the supporting floor when the folded treadmill is to be moved from one place to another. This is laborious and inconvenient.
An object of the invention is to provide a foldable treadmill which can address the problems described hereinabove.
Another object of the invention is to provide a tread mill with a stable foldable support structure to support a tread base.
According to the present invention, a treadmill which can be folded to an inoperative position and unfolded to an operative position, comprises a tread base having a front end, and a first foot unit disposed at the front end; and a pair of rear links having front ends pivotally connected to the tread base about a first pivot axis posterior to the first foot unit, and rear ends provided with a second foot unit. The rear links are pivotal relative to the tread base to move the second foot unit towards the tread base when the treadmill is at the operative position and away from the tread base when the treadmill is at the inoperative position. The treadmill further comprises: a console assembly including a pair of posts extending upward from the tread base adjacent the front end of the tread base and pivoted to the tread base respectively at left and right sides of the tread base about a second pivot axis, and a console panel attached to top ends of the posts; and a pair of coupling arms having front ends respectively connected to the posts and rear ends respectively connected to the rear links between the front and rear ends of the rear links.